S&W M&P10 - From Stock to Not

[Spata]

My thoughts were to swap it as well. Think swapping the springs would help or go the full monte?

ETA: Please no .gifs.

I went swapped it all out.

 

[Gabriel42]

I went swapped it all out.

I do have an SSA-E sitting around here somewhere.

 

[farmerbyron]

Added Vortex Viper PST 4-16x50 in ADM mount, new weight is 12lbs 14oz.

Looks good. Curious to see what it will do at a more suitable range.

 

[Gabriel42]

Looks good. Curious to see what it will do at a more suitable range.

Should be able to make it out to Banner on Thursday to see what it'll do at 100 yds. Hoping to get out to OKCGC at some point in the near future to stretch it out a bit farther.

 

[Gabriel42]

Made it out to Canadian Valley Ranges today. Took 3 boxes of HPR 168gr BTHP Match .308 ammo. I have had great luck in the past with .380ACP,9mm, .45ACP, and .223 ammo from HPR. It is uniform, accurate and clean. I started at 25yds to make sure I was on paper and then moved out. Groups are below.

25yds

50yds

100yds (Extracting cases with cleaning rod is frustrating and causes big groups, more on that below.)

Shot 3 rounds at 25yds, 3 rounds at 50yds and then moved to the 100yd line. Shot 6 rounds, dialing in the scope after each string of 3. The 13th round of the day is where it all went to sh*t. 8 of the last 10 rounds I shot did not extract because the extractor ripped off the lip of the case. Additionally, 1 of the 8 that did not extract had the primer blow out. Pic is below. A guy shooting next to me was kind enough to hand me a LC cased load and while it didn't rip the case lip, there was a definite attempt to bend it made on behalf of the extractor.

My thoughts are that it is still overgassed. I did not make any adjustments after the range trip on Monday and seem to have misplaced the provided 2mm ball Allen wrench that came with the block. Related note: 2mm ball driver will be delivered tomorrow afternoon.

Taking the rifle down and inspecting it tonight and taking it in to work tomorrow to have the gunsmith and another guy take a look. Will update with findings.

Also, anyone know of a good iPhone app that does the shot group measurement from a picture?

 

[grwd]

how did you adjust the gas?

 

[Gabriel42]

how did you adjust the gas?

Reports are the gun comes under-gassed from the factory. Gas port started off at .068. Only thing I have 'adjusted' so far in the gas system is having the barrel cutdown 3.5" and suppressing it. I have a SLR Rifleworks adjustable gas block on the rifle and that will be dialed in today. Headed to the store right after I post this reply, actually

1st range trip it saw 20rds of GGG (Lithuanian) surplus 7.62x51 with no extraction issues but 2 FTF (light primer strike, fired 2nd go around.

2nd range trip was where the extraction issues and ripped cases happened using HPR 168gr BTHP Match .308.

 

[grwd]

interesting build.

Ill be curious to see what works.

so going from 18" to 14.5"
is it a rifle length system, or some intermediate length tube?
All shots thus far were suppressed?

most .308 match stuff is pretty hot for an ar-10, so the 168gr ripping rims isnt too suprising.
If you can find a spot where turning down the gas gets it reliable, both suppressed, unsuppressed, and shooting milder 7.62 and hotter .308 stuff; awesome, but I think you might have to keep it to certain kinds of ammo, or reload. A Heavy buffer, or putting a rifle stock and buffer system in it are possiblities if you have to wring it out a little longer than you may have hoped to.

good luck!

 

[Gabriel42]

interesting build.

Ill be curious to see what works.

so going from 18" to 14.5"
is it a rifle length system, or some intermediate length tube?
All shots thus far were suppressed?

most .308 match stuff is pretty hot for an ar-10, so the 168gr ripping rims isnt too suprising.
If you can find a spot where turning down the gas gets it reliable, both suppressed, unsuppressed, and shooting milder 7.62 and hotter .308 stuff; awesome, but I think you might have to keep it to certain kinds of ammo, or reload. A Heavy buffer, or putting a rifle stock and buffer system in it are possiblities if you have to wring it out a little longer than you may have hoped to.

good luck!

Yes, 18 to 14.25-ish" with a permanently attached AAC 51T FH mount, it is a mid-length gas system, and all 44 (20 - 7.62 and 22 - .308 (8ripped)) shots so far have been suppressed with a AAC 762-SDN-6.

As you said, the holy grail would be a setting where 7.62 and .308 function, suppressed and unsuppressed, but that is unlikely. I am hoping I can locate the 4 gas block settings for one .308 load and one 7.62 load, suppressed and unsuppressed, and just make adjustments based on the need and round I am shooting on whatever day.

 

[Parks 788]

Thank you!





So the new rails are only available through Troy for pre-order. I called and talked to one of their sales/CSR people, Denise, and ordered both of them, figuring that I would just cancel the VTAC if I found the Alpha suitable. When I got the confirmation, I was surprised by a note from her saying that their Memorial Day sale had just ended but she had gone ahead and given me the discount so I saved 25% instead of 10% for the .mil discount. I will now wait until I have both and make a decision and sell the other. There are a number of other options out there I would love to have but most don't come in .308 versions.

I also got the scope today; a lot quicker turnaround than I thought. Vortex Viper PST 4-16x50 SFP.

Rifle looks great so far. I have the same scope but in 1-4x30 on my Mini 14 and the ejected brass is hell on the turret. Any issues with your M&P and those huge turrets?